The F# repl (FSI as fsharp interactive) works in .net core 3.0 preview already, you can do `dotnet fsi` to run it
Type providers works in general, but depends if the type provider library was updated to use latest type provider sdk.
Also generative type provider may not works, erasing works
Enrico answered to question w.r.t where F# is now, but F# is going to also be a big part of .NET 5. The only reason it's not mentioned in the post is that we haven't firmly decided on if the F# release that corresponds with .NET 5 will version in lockstep like C# is planned to do.
Type providers works in general, but depends if the type provider library was updated to use latest type provider sdk. Also generative type provider may not works, erasing works